Pipe reamer



April 17, 1934. p w -r 1,955,447

PI PE REAMER Filed Jan. 22, 1931 I BY W2M ATTORNEYS.

Patented Apr. 17, 1934 PATENT OFFICE PIPE REAMER Ross P. Wright, Erie, Pa.,

assignor 'to Reed Manufacturing Company, Erie, .Pa.,. a corporation of Pennsylvania Application January 22, 1931, Serial No. 510,356

9 Claims.

In the cutting of pipe under ordinary methods of cutting, a burr is formed on the inner edge of the opening. This burr quite materially reduces the cross area of the pipe and consequently its capacity. Nearly all plumbing "specifications require the removal of this burr, but it has been difficult to enforce these specifications because of the dimculty heretofore experienced in accomplishing the removal of the burr.

In providing tools for this purpose the .most common reamer is provided with a series of cutting blades, the cutting edges of which are in axial planes and are tapered so that a single Cutter may be used for several sizes of pipe and w the taper facilitates the cut for each size. This tool not only requires the effort of turning the tool .in order to make the circumferential cut,

but it is also necessary to exert sufiicient axial pressure upon the tool to force, or induce the 0 cut. With .reamers of a very slight taper the cutting edge has been formed in a spiral, but in a direction against the feeding action, the purpose apparently being to prevent the wedging of the tool as it is crowded to its work.

In any of these tools the effort to advance the tool varies very materially with the sharpness of the cutting edge so that with the tools as heretofore made if the cutting edge is slightly dull the effort to advance it to effect a feed becomes very great as the tool becomes dull.

The present invention is designed to avoid these dficulties and it is accomplished by providing a cutting edge with a self-feeding spiral, that is, a pitch toward the right so that as the reamer is rotated it tends to work into the pipe. With such a cutting edge if the cutting edge is sharp the self-feeding may be too pronounced and thus block the turning of the device. On the other hand, with the same spiral with the 40 cutting edge dull the self-feeding action may be lost. With the present invention I provide a self-feeding edge preferably with a pitch that will over-feed at least with the cutting edge sharp so that with practically all conditions of the cutting edge there is a positive self-feeding action of the cutting edge and, according to the present invention, the cut is definitely controlled by providing limiting surfaces between the cutting edges which control the depth of the cut regardless of the sharpness of the cutting edge so that the out can be readily handled by the operator. Features and details of the invention will appear from the specification and claims.

A preferred embodiment of the invention is illustrated in the accompanying drawing as follows:-

Fig 1 shows a central section through the device in operative position.

Fig. 2 an enlarged view 'of the reamer proper.

Fig. 3 a section on the line 3-3 in Fig. 2.

'1 marks a pipe having a burred end, '2 a reamer, 3 a ratchet body, the ratchet body being provided with a projection 4 extending into a socket 5 in the rear end of the reamer. The shoulder 4 has a projection 6 engaging a shoulder 6a in the interior of the reamer body, thus keying the ring body with the reamer. A pipe projection '7 extends into a socket 8 in the ratchet body 3. A shell 9 is arranged over the proiiec- T0 tion "7 and terminates in a head 10. A rod 11 is secured on the head '10 and has a screwthreaded 'end which is secured in a screwthreaded socket 12 in the interior of the reamer, the reamer body'being hollow. "This shell 9 forms a handle by means of which the operator holds the reamer in an axial position relatively to the pipe. The reamer is'such that practically no endw'ise pressure is necessary even for starting the reamer. 1.9

A ratchet ring 13 is mounted 'on the body 3 and a pawl 14 extends into a groove "15 in the body, thus holding the ring on the body, and 0perates on ratchet teeth 15a in the ordinary man'- her of a ratchet pawl. The pawl is yieldingly forced forward by a spring 16 and is reversible in the manner common to pawls of this type. An operating handle 17 extends from the ring 13.

The reamer body is provided with cutting edges 18. These cutting edges are arranged on the spiral, the pitch of which is sufficient to assure a feeding action through the engagement of the cutting edge with the work.

The angle shown in the drawing is between 20 and 30 and the taper ofthe'ream'er overall is approximately 23. This angle of cutting edge with a taper such as shown will readily accomplish self-feeding in steel pipe. A chip groove 19 extends along the front of each cutting edge and a cut-limiting surface 20 extends between the groove and a point preferably immediately to the rear of the cutting edge. This cut-limiting surface is of slightly less radial dimension than the cutting edge 18, thus controlling the depth of the cut of the cutting edge to exactly the projection I05 of the cutting edge beyond the surface 20. This relation is clearly illustrated in Fig. 3. In this way the depth of the cut may be definitely controlled. It is possible, therefore, to give to the cutting edge a self-feeding spiral quite materiice ally in excess of what would be necessary to assure a self-feeding action and quite materially in excess of the angle shown in the drawing. This spiral, as clearly shown in Fig. 2, is in a right-hand direction so as to be self-feeding when the reamer is turned in a right-hand direction and the pitch of the spiral is such as to give a definite self-feeding action even when the cutting edges are quite dull. Thus the reamer will immediately grab the burr when put into place and turned, but will not gouge in so as to block the turning of the reamer. In other words, the cut is so controlled as to provide for the most convenient turning effort.

In order to balance the self-feeding feature of the spiral along different portions of the reamer, the angle of the spiral of the cutting edge to an axial plane is made approximately constant throughout the length of the reamer. This differs quite materially from an ordinary thread spiral of uniform pitch.

With this structure the reaming of pipe is a very simple operation, the physical effort being only a fraction of what has been necessary with previous tools and one that may be used with ease even after the cutting edge is quite dull, thus permitting a long-continued use without servicing.

What I claim as new is:-

l. A pipe reamer having a tapered body with a peripheral cutting edge forwardly inclined toward the smaller end of and extending in a selffeeding spiral on the tapered body, and a cutlimiting surface on the body having a lesser radius than the edge, controlling the out of the edge to a depth to prevent gouging by the reamer and to assure self-feeding.

2. A pipe reamer having a tapered body with a plurality of peripheral cutting edges forwardly inclined toward the smaller end of and extending in self-feeding spirals and cut-limiting surfaces on the body having lesser radii than the edges controlling the cut of the edges to a depth to prevent gouging by the reamer and to assure self-feeding.

3. A pipe reamer having a tapered body with a peripheral cutting edge forwardly inclined toward the smaller end of and extending in a selffeeding spiral, and a cut-limiting surface on the body having a lesser radius than the edge, controlling the cut of the edge to a depth to prevent gouging by the reamer and to assure self-feeding, the body being provided with a chip-receiving groove in front of the cutting edge.

4. A pipe reamer having a tapered body with a plurality of peripheral cutting edges forwardly inclined toward the smaller end of and extending in self-feeding spirals and cut-limiting surfaces on the body having lesser radii than the edges controlling the out of the edges to a depth to prevent gouging by the reamer and to assure self-feeding, the body being provided with chipreceiving grooves in front of the cutting edges.

5. A pipe reamer having a tapered body with a peripheral cutting edge forwardly inclined toward the smaller end of and extending in a selffeeding spiral, the angle of the spiral to an axial plane being approximately constant throughout its length, and a cut-limiting surface on the body having a lesser radius than the edge, controlling the cut of the edge to a depth to prevent gouging by the reamer and to assure self-feeding.

6. A pipe reamer having a tapered body with a plurality of peripheral cutting edges forwardly inclined toward the smaller end of and extending in self-feeding spirals on the tapered body, the angles of the spirals to axial planes being approximately constant throughout the length of the spirals, and cut-limiting surfaces on the body having lesser radii than the edges controlling the cut of the edges to a depth to prevent gouging by the reamer and to assure self-feeding.

'7. A pipe reamer having a tapered body with a peripheral cutting edge forwardly inclined toward the smaller end of and extending in a selffeeding spiral, and a cut-limiting surface on the body having a lesser radius than the edge, controlling the cut of the edge to a depth to prevent gouging by the reamer and to assure selffeeding, in combination with a ratchet head secured to the reamer, and a handle in line with the axis of the reamer.

8. In a pipe reamer, the combination of a reamer having a tapered body with a peripheral cutting edge forwardly inclined toward the smaller end of and extending in a self-feeding spiral on the tapered body; a cut-limiting surface on the body having a lesser radius than the edge controlling the cut of the edge to a depth to prevent gouging by the reamer and to assure a selffeeding, said body having a screw socket at its axis; a ratchet body having a projecting shoulder extending into the reamer body; a handle on the ratchet body in alinement with the axis of the reamer; a ratchet ring operating on the ratchet body; a handle shell on the handle; and a bolt extending from the handle shell through the handle into the screw socket in the reamer.

9. In a pipe reamer, the combination of a reamer having a tapered body with a cutting edge forwardly inclined toward the smaller end of and extending in a self-feeding spiral; a cutlimiting surface on the body having a lesser radius than the edge controlling the cut of the edge to a depth to prevent gouging by the reamer and to assure a self-feeding, said body having a screw socket at its axis; a ratchet body having a projecting shoulder extending into the reamer body; a handle on the ratchet body in alinement with the axis of the reamer; a ratchet ring operating on the ratchet body; a handle shell on the handle; a bolt extending from the handle shell through the handle into the screw socket in the reamer; a ratchet device; and a screw extending through the device into the screw socket for securing the ratchet device.

ROSS P. WRIGHT. 

